PT - JOURNAL ARTICLE ED - American Society of Neuroradiology TI - Letters DP - 1991 Sep 01 TA - American Journal of Neuroradiology PG - 1023--1027 VI - 12 IP - 5 4099 - http://www.ajnr.org/content/12/5/1023.2.short 4100 - http://www.ajnr.org/content/12/5/1023.2.full SO - Am. J. Neuroradiol.1991 Sep 01; 12